1
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Sardar G, Biswas A, Singh S, Kabra D. Study of Intrachain Charge Transfer in a Blue Emissive Polyfluorene Random Copolymer. J Phys Chem B 2024; 128:3521-3526. [PMID: 38547519 DOI: 10.1021/acs.jpcb.4c00767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024]
Abstract
Photophysics of a blue light-emitting fluorescent random copolymer, consisting of arylated polydioctylfluorene (aryl-F8), polydioctylfluorene (F8), and amine comonomers in a ratio of 80:15:5 is reported. In a solution of 10-6 M, solvatochromism in absorption and photoluminescence (PL) is observed with an increased lifetime of PL as the polarity of the solvent increases. Dual fluorescence is observed in the 10-9 M diluted solution, comprising a structured emission from a localized state in the aryl-F8 comonomer and a broad emission peak from the charge-transfer (CT) state at a lower energy. Emission wavelength-dependent time-resolved photoluminescence studies in different polar media confirm the presence of the emissive intrachain CT state in this copolymer. Analyzing the PL decay kinetics, we calculated the formation rate of the intrachain CT state to be ∼3.0 × 109 s-1. Repopulation of the localized state from the CT state is observed in the lower polarity medium with a rate of 7 × 108 s-1, which is almost absent for the large Stokes-shifted CT emission in the higher polarity medium. Along with the fundamental understanding of the photophysics of the random copolymer, this study suggests that the emission spectrum can be tailored by the concentration of polymer and the polarity of surrounding media.
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Affiliation(s)
- Gopa Sardar
- Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Abhinav Biswas
- Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Shivam Singh
- Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076, India
- Chair for Emerging Electronic Technologies, TUD Dresden University of Technology, Nöthnitzer Str. 61, Dresden 01187, Germany
| | - Dinesh Kabra
- Department of Physics, Indian Institute of Technology Bombay, Mumbai 400076, India
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2
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Li D, He X, Zhao L, Jia M, Li H, Zhang S, Zhang X, Chen J, Jin Q, Xu J. Ultrafast Electron Transfer Dynamics of Organic Polymer Nanoparticles with Graphene Oxide. Chemistry 2023; 29:e202300025. [PMID: 36691919 DOI: 10.1002/chem.202300025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 01/25/2023]
Abstract
We prepared organic polymer poly-3-hexylthiophene (p3ht) nanoparticles (NPs) and graphene oxide (GO)/reduced graphene oxide (RGO) composites p3ht NPs-GO/RGO by using the reprecipitation method. We demonstrated that GO/RGO could improve the ordering and planarity of p3ht chains as well as the formation of p3ht NPs, and confirmed the effects of GO/RGO on the fluorescence and carrier transport dynamics of p3ht NPs by using femtosecond fluorescence upconversion and transient absorption (TA) techniques. Ultrafast electron transfer (∼1 ps) between GO/RGO and p3ht NPs quenched the fluorescence of p3ht NPs, indicating excellent properties of p3ht NPs-GO/RGO as the charge transfer complexes. Efficient electron transfer may promote the applications of p3ht NPs-GO/RGO composites in organic polymer solar cells and photocatalysis. Moreover, RGO had stronger interfacial interactions and more matched conduction band energy levels with p3ht NPs than GO did, which implied that p3ht NPs-RGO might have greater application values than p3ht NPs-GO.
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Affiliation(s)
- Dong Li
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
| | - Xiaoxiao He
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
| | - Litao Zhao
- Key Laboratory of Spin Electron and Nanomaterials of, Anhui Higher Education Institutes, Suzhou University, 49 Bianhe Middle Road, Suzhou, 234000, P. R. China
| | - Menghui Jia
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
| | - Haoyang Li
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
| | - Sanjun Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
| | - Xiaolei Zhang
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
| | - Jinquan Chen
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
| | - Qingyuan Jin
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
| | - Jianhua Xu
- State Key Laboratory of Precision Spectroscopy, East China Normal University, 500 Dongchuan Road, Shanghai, 200241, P. R. China
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3
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Hamilton I, Suh M, Bailey J, Bradley DDC, Kim JS. Optimizing Interfacial Energetics for Conjugated Polyelectrolyte Electron Injection Layers in High Efficiency and Fast Responding Polymer Light Emitting Diodes. ACS APPLIED MATERIALS & INTERFACES 2022; 14:24668-24680. [PMID: 35583466 PMCID: PMC9164195 DOI: 10.1021/acsami.2c05640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
Modification of the π-conjugated backbone structure of conjugated polyelectrolytes (CPEs) for use as electron injection layers (EILs) in polymer light emitting diodes (PLEDs) has previously brought conflicted results in the literature in terms of device efficiency and turn-on response time. Herein, we determine the energetics at the CPE and the light emitting polymer (LEP) interface as a key factor for PLED device performance. By varying the conjugated backbone structure of both the LEP and CPE, we control the nature of the CPE/LEP interface in terms of optical energy gap offset, interfacial energy level offset, and location of the electron-hole recombination zone. We use a wide gap CPE with a shallow LUMO (F8im-Br) and one with a smaller gap and deeper LUMO (F8imBT-Br), in combination with three different LEPs. We find that the formation of a type II heterojunction at the CPE/LEP interfaces causes interfacial luminance quenching, which is responsible for poor efficiency in PLED devices. The effect is exacerbated with increased energy level offset from ionic rearrangement and hole accumulation occurring near the CPE/LEP interface. However, a deep CPE LUMO is found to be beneficial for fast current and luminance turn-on times of devices. This work provides important CPE molecular design rules for EIL use, offering progress toward a universal PLED-compatible CPE that can simultaneously deliver high efficiency and fast response times. In particular, engineering the LUMO position to be deep enough for fast device turn-on while avoiding the creation of a large energy level offset at the CPE/LEP interface is shown to be highly desirable.
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Affiliation(s)
- Iain Hamilton
- Department
of Physics and Centre for Processable Electronics, Imperial College London, London SW7 2AZ, United Kingdom
- Division
of Physical Sciences and Engineering, King
Abdullah University of Science and Technology (KAUST), Thuwal, 23955−6900 Saudi Arabia
| | - Minwon Suh
- Department
of Physics and Centre for Processable Electronics, Imperial College London, London SW7 2AZ, United Kingdom
| | - Jim Bailey
- Department
of Physics and Centre for Processable Electronics, Imperial College London, London SW7 2AZ, United Kingdom
| | - Donal D. C. Bradley
- Division
of Physical Sciences and Engineering, King
Abdullah University of Science and Technology (KAUST), Thuwal, 23955−6900 Saudi Arabia
| | - Ji-Seon Kim
- Department
of Physics and Centre for Processable Electronics, Imperial College London, London SW7 2AZ, United Kingdom
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4
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Yan H, Tseng TW, Omagari S, Hamilton I, Nakamura T, Vacha M, Kim JS. Dynamic Molecular Conformational Change Leading to Energy Transfer in F8-5% BSP Copolymer Revealed by Single-Molecule Spectroscopy. J Chem Phys 2022; 156:074704. [DOI: 10.1063/5.0080406] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Hao Yan
- Peking University Shenzhen Graduate School School of Advanced Materials, China
| | - Tzu-Wei Tseng
- Tokyo Institute of Technology Department of Materials Science and Engineering, Japan
| | - Shun Omagari
- Tokyo Institute of Technology Department of Materials Science and Engineering, Japan
| | - Iain Hamilton
- King Abdullah University of Science and Technology Physical Sciences and Engineering Division, Saudi Arabia
| | - Tomonori Nakamura
- Tokyo Institute of Technology Department of Materials Science and Engineering, Japan
| | - Martin Vacha
- Department of Materials Science and Engineering, Tokyo Institute of Technology - Ookayama Campus, Japan
| | - Ji-Seon Kim
- Physics, Imperial College London, United Kingdom
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5
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Cheng Z, O'Carroll DM. Photon Recycling in Semiconductor Thin Films and Devices. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2004076. [PMID: 34411461 PMCID: PMC8529496 DOI: 10.1002/advs.202004076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 05/10/2021] [Indexed: 06/02/2023]
Abstract
Photon recycling (PR) plays an important role in the study of semiconductor materials and impacts the properties of their optoelectronic applications. However, PR has not been investigated comprehensively and it has not been demonstrated experimentally in many different kinds of semiconductor materials and devices. In this review paper, first, the authors introduce the background of PR and describe how this phenomenon was originally identified in semiconductors. Then, the theory and modelling of PR is reviewed and some of the important parameters that are used to quantify PR are highlighted. Next, a variety of the methods used to achieve and characterize PR in materials and devices are discussed. Examples of how the performance parameters of different types of optoelectronic devices are affected by PR are described. Finally, a summary of the roles of PR in semiconductor materials and devices and an outlook on how PR can be used to solve existing problems and challenges in the field of optoelectronics are provided. From this review, it is apparent that PR can have a positive impact on optoelectronic device performance, and that further in-depth theoretical and experimental studies are needed to rigorously demonstrate the advantages and importance of PR.
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Affiliation(s)
- Zhongkai Cheng
- Department of Chemistry and Chemical BiologyRutgers University123 Bevier RoadPiscatawayNJ08854USA
| | - Deirdre M. O'Carroll
- Department of Chemistry and Chemical BiologyRutgers University123 Bevier RoadPiscatawayNJ08854USA
- Department of Materials Science and EngineeringRutgers University607 Taylor RoadPiscatawayNJ08854USA
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6
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Fortino M, Cozza C, Bonomi M, Pietropaolo A. Multi-replica biased sampling for photoswitchable π-conjugated polymers. J Chem Phys 2021; 154:174108. [PMID: 34241080 DOI: 10.1063/5.0045944] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In recent years, π-conjugated polymers are attracting considerable interest in view of their light-dependent torsional reorganization around the π-conjugated backbone, which determines peculiar light-emitting properties. Motivated by the interest in designing conjugated polymers with tunable photoswitchable pathways, we devised a computational framework to enhance the sampling of the torsional conformational space and, at the same time, estimate ground- to excited-state free-energy differences. This scheme is based on a combination of Hamiltonian Replica Exchange Method (REM), parallel bias metadynamics, and free-energy perturbation theory. In our scheme, each REM samples an intermediate unphysical state between the ground and the first two excited states, which are characterized by time-dependent density functional theory simulations at the B3LYP/6-31G* level of theory. We applied the method to a 5-mer of 9,9-dioctylfluorene and found that upon irradiation, this system can undergo a dihedral inversion from -155° to 155°, crossing a barrier that decreases from 0.1 eV in the ground state (S0) to 0.05 eV and 0.04 eV in the first (S1) and second (S2) excited states. Furthermore, S1 and even more S2 were predicted to stabilize coplanar dihedrals, with a local free-energy minimum located at ±44°. The presence of a free-energy barrier of 0.08 eV for the S1 state and 0.12 eV for the S2 state can trap this conformation in a basin far from the global free-energy minimum located at 155°. The simulation results were compared with the experimental emission spectrum, showing a quantitative agreement with the predictions provided by our framework.
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Affiliation(s)
- Mariagrazia Fortino
- Dipartimento di Scienze Della Salute, Università di Catanzaro, Viale Europa, 88100 Catanzaro, Italy
| | - Concetta Cozza
- Dipartimento di Scienze Della Salute, Università di Catanzaro, Viale Europa, 88100 Catanzaro, Italy
| | - Massimiliano Bonomi
- Structural Bioinformatics Unit, Department of Structural Biology and Chemistry; CNRS UMR 3528; C3BI, CNRS USR 3756; Institut Pasteur, Paris, France
| | - Adriana Pietropaolo
- Dipartimento di Scienze Della Salute, Università di Catanzaro, Viale Europa, 88100 Catanzaro, Italy
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7
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Optical Gain in Semiconducting Polymer Nano and Mesoparticles. Molecules 2021; 26:molecules26041138. [PMID: 33672710 PMCID: PMC7924374 DOI: 10.3390/molecules26041138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 02/16/2021] [Accepted: 02/17/2021] [Indexed: 11/22/2022] Open
Abstract
The presence of excited-states and charge-separated species was identified through UV and visible laser pump and visible/near-infrared probe femtosecond transient absorption spectroscopy in spin coated films of poly[N-9″-heptadecanyl-2,7-carbazole-alt-5,5-(4,7-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) nanoparticles and mesoparticles. Optical gain in the mesoparticle films is observed after excitation at both 400 and 610 nm. In the mesoparticle film, charge generation after UV excitation appears after around 50 ps, but little is observed after visible pump excitation. In the nanoparticle film, as for a uniform film of the pure polymer, charge formation was efficiently induced by UV excitation pump, while excitation of the low energetic absorption states (at 610 nm) induces in the nanoparticle film a large optical gain region reducing the charge formation efficiency. It is proposed that the different intermolecular interactions and molecular order within the nanoparticles and mesoparticles are responsible for their markedly different photophysical behavior. These results therefore demonstrate the possibility of a hitherto unexplored route to stimulated emission in a conjugated polymer that has relatively undemanding film preparation requirements.
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8
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Chen J, Zhang Y, Lin Z, Shen J, George TF, Li S. Photoexcitation-induced local phonon spectra and local hot excitons in polymer solar cells. OPTICS EXPRESS 2020; 28:1385-1393. [PMID: 32121850 DOI: 10.1364/oe.28.001385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/25/2019] [Indexed: 06/10/2023]
Abstract
In this article, based on nonadiabatic molecular dynamics with electronic transitions, the elaborate ultrafast process of hot excitons in conjugated polymer solar cells is revealed. When an external optical beam/pulse with the intensity of 30 µJ/cm-2 is utilized to excite a conjugated polymer, just within only 50 fs, the electronic transition not only redistributes the electron population in the original molecular orbital, but also starts to localize the electron cloud of excited states and to distort the alternating bonds in the polymer chain. Up to 300 fs, the lattice distortion has been stabilized. During the formation of hot excitons, the prominent self-trapping effect of conjugated polymer triggers the occurrence of local infrared active phonon modes, with five peaks in the phonon spectrum as the hot excitons relax. The characteristic phonon spectrum and infrared modes hence form the fingerprint of the hot excitons of a conjugated polymer, which are readily distinguished from other excitation states in the polymer.
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9
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Abelha TF, Dreiss CA, Green MA, Dailey LA. Conjugated polymers as nanoparticle probes for fluorescence and photoacoustic imaging. J Mater Chem B 2020; 8:592-606. [DOI: 10.1039/c9tb02582k] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In this review, the role of conjugated polymer nanoparticles (CPNs) in emerging bioimaging techniques is described.
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Affiliation(s)
- Thais Fedatto Abelha
- King's College London
- Institute of Pharmaceutical Science
- London
- UK
- School of Pharmacy
| | - Cécile A. Dreiss
- King's College London
- Institute of Pharmaceutical Science
- London
- UK
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10
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Cheng G, Kwak Y, To WP, Lam TL, Tong GSM, Sit MK, Gong S, Choi B, Choi WI, Yang C, Che CM. High-Efficiency Solution-Processed Organic Light-Emitting Diodes with Tetradentate Platinum(II) Emitters. ACS APPLIED MATERIALS & INTERFACES 2019; 11:45161-45170. [PMID: 31718137 DOI: 10.1021/acsami.9b11715] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The realization of high-efficiency solution-processed organic light-emitting diodes (OLEDs) using phosphorescent tetradentate Pt(II) emitters and bipolar organic hosts is demonstrated in this work. To investigate the effect of organic host on the platinum dopant, the performances of solution-processed Pt-OLEDs with various combinations between four tetradentate Pt(II) emitters, including two newly developed tetra-Pt-S2 and tetra-Pt-S3 and three bipolar organic hosts m-TPAPy, o-TPAPy, and o-CzPy, have been analyzed and compared. Among the tetradentate Pt(II) complexes studied in this work, tetra-Pt-S3 exhibited the best electroluminescent performance attributable to its bulky molecular scaffold structure, high emission quantum yield, and good solubility in common organic solvents. High external quantum efficiencies (EQEs) of up to 22.4% were achieved in the solution-processed OLED with tetra-Pt-S3 emitter and m-TPAPy host at the dopant concentration of 4 wt %. At a high luminance of 1000 cd m-2, the EQE of this device decreased slightly to 21.0%.
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Affiliation(s)
- Gang Cheng
- HKU Shenzhen Institute of Research and Innovation , Shenzhen 518053 , P. R. China
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , P. R. China
| | - Yoonhyun Kwak
- Samsung Electronics, Organic Material Lab, SAIT , 130 Samsung-ro , Yeongtong-gu, Suwon-si , Gyeonggi-do 16678 , Korea
| | - Wai-Pong To
- HKU Shenzhen Institute of Research and Innovation , Shenzhen 518053 , P. R. China
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , P. R. China
| | - Tsz-Lung Lam
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , P. R. China
| | - Glenna So Ming Tong
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , P. R. China
| | - Man-Ki Sit
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , P. R. China
| | - Shaolong Gong
- Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China
| | - Byoungki Choi
- Samsung Electronics, Organic Material Lab, SAIT , 130 Samsung-ro , Yeongtong-gu, Suwon-si , Gyeonggi-do 16678 , Korea
| | - Wha Il Choi
- Samsung Electronics, Samsung Research Funding & Incubation Center for Future Technology Seoul R&D Campus , Umyeon dong 33, Seongchon-gil , Seocho-gu, Seoul 06765 , Korea
| | - Chuluo Yang
- Hubei Key Lab on Organic and Polymeric Optoelectronic Materials, Department of Chemistry , Wuhan University , Wuhan 430072 , P. R. China
| | - Chi-Ming Che
- HKU Shenzhen Institute of Research and Innovation , Shenzhen 518053 , P. R. China
- State Key Laboratory of Synthetic Chemistry, HKU-CAS Joint Laboratory on New Materials, and Department of Chemistry , The University of Hong Kong , Pokfulam Road , Hong Kong SAR , P. R. China
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11
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Kumar S, Malik V, Shukla J, Kumar Y, Bansal D, Chatterjee R, Mukhopadhyay P. Ionic Assembly, Anion–π, Magnetic, and Electronic Attributes of Ambient Stable Naphthalenediimide Radical Ions. Chemistry 2019; 25:4740-4750. [DOI: 10.1002/chem.201805978] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/30/2019] [Indexed: 12/12/2022]
Affiliation(s)
- Sharvan Kumar
- Supramolecular and Material Chemistry LabSchool of Physical SciencesJawaharlal Nehru University New Delhi 110067 India
| | - Vikas Malik
- Department of PhysicsIndian Institute of Technology, Delhi, New Delhi 110016 India
| | - Jyoti Shukla
- Supramolecular and Material Chemistry LabSchool of Physical SciencesJawaharlal Nehru University New Delhi 110067 India
| | - Yogendra Kumar
- Supramolecular and Material Chemistry LabSchool of Physical SciencesJawaharlal Nehru University New Delhi 110067 India
| | - Deepak Bansal
- Supramolecular and Material Chemistry LabSchool of Physical SciencesJawaharlal Nehru University New Delhi 110067 India
| | - Ratnamala Chatterjee
- Department of PhysicsIndian Institute of Technology, Delhi, New Delhi 110016 India
| | - Pritam Mukhopadhyay
- Supramolecular and Material Chemistry LabSchool of Physical SciencesJawaharlal Nehru University New Delhi 110067 India
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12
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Kumar P, Vahidzadeh E, Thakur UK, Kar P, Alam KM, Goswami A, Mahdi N, Cui K, Bernard GM, Michaelis VK, Shankar K. C3N5: A Low Bandgap Semiconductor Containing an Azo-Linked Carbon Nitride Framework for Photocatalytic, Photovoltaic and Adsorbent Applications. J Am Chem Soc 2019; 141:5415-5436. [DOI: 10.1021/jacs.9b00144] [Citation(s) in RCA: 253] [Impact Index Per Article: 50.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Pawan Kumar
- Department of Electrical and Computer Engineering, University of Alberta, 9211 116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Ehsan Vahidzadeh
- Department of Electrical and Computer Engineering, University of Alberta, 9211 116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Ujwal K. Thakur
- Department of Electrical and Computer Engineering, University of Alberta, 9211 116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Piyush Kar
- Department of Electrical and Computer Engineering, University of Alberta, 9211 116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Kazi M. Alam
- Department of Electrical and Computer Engineering, University of Alberta, 9211 116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Ankur Goswami
- Department of Electrical and Computer Engineering, University of Alberta, 9211 116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Najia Mahdi
- Department of Electrical and Computer Engineering, University of Alberta, 9211 116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Kai Cui
- Nanotechnology
Research Centre, National Research Council of Canada, Edmonton, Alberta T6G 2M9, Canada
| | - Guy M. Bernard
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | | | - Karthik Shankar
- Department of Electrical and Computer Engineering, University of Alberta, 9211 116 Street, Edmonton, Alberta T6G 1H9, Canada
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Dey A, Kabra D. Role of Bimolecular Exciton Kinetics in Controlling the Efficiency of Organic Light-Emitting Diodes. ACS APPLIED MATERIALS & INTERFACES 2018; 10:38287-38293. [PMID: 30298717 DOI: 10.1021/acsami.8b10559] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Here, we have carried out a spectroscopic investigation on the operational organic light-emitting diodes (OLEDs) to determine the role of emission layer thickness on the optoelectronic performance of OLEDs based on a poly(9,9-dioctylfluorene- alt-benzothiadiazole) (F8BT) copolymer system. Our study shows that delayed fluorescence (DF) via triplet-triplet annihilation (TTA) contributes significantly to boost the OLED efficiency through its fractional contribution. Interestingly, we note that DF contribution varies as a function of the emissive layer thickness. From the time-resolved electroluminescence (TREL) and triplet absorption (under electrical excitation) studies, we have seen that the emissive layer thickness controls triplet exciton generation and decay processes. From TREL, we have also shown that singlet-triplet annihilation (STA) is the dominant fluorescence quenching mechanism in bulk of the emissive layer, whereas thinner devices have significant exciton quenching at the interface of the injection layer/F8BT. The strength of STA differs in thin versus thick samples, which has been correlated with the spectral & spatial overlap integral of singlet and triplet states. Hence, STA strength and triplet population density are critical parameters for an explanation of high efficiency in unusually thick F8BT OLEDs.
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Affiliation(s)
- Amrita Dey
- Department of Physics , Indian Institute of Technology Bombay , Powai, Mumbai 400076 , India
| | - Dinesh Kabra
- Department of Physics , Indian Institute of Technology Bombay , Powai, Mumbai 400076 , India
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14
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Cozza C, Bonomi M, Pietropaolo A. A Versatile Computational Strategy To Characterize the Free-Energy Landscape of Excited States in Oligofluorenes. J Chem Theory Comput 2018; 14:5441-5445. [PMID: 30365313 DOI: 10.1021/acs.jctc.8b00949] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The π-rich rings of conjugated polymers and molecular rotors shape their typical properties, allowing a variety of chemical and photoresponsive phenomena. Herein, we present a computational method in the framework of classical simulations to estimate the free-energy gap between ground and excited states of oligofluorenes, which is a class of molecular rotors widely used in optoelectronic devices, because of the inner torsional rotation triggered by light irradiation. We devised multiple sets of free-energy simulations in combination with free-energy perturbation theory to predict the free-energy gap between the ground state and the first excited state. The computed excitation energies show good agreement with experiments. The approach presented herein allows one to achieve comprehensive sampling of the conformational landscape and accurate estimates of the excited state free-energy landscapes at the same time.
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Affiliation(s)
- Concetta Cozza
- Dipartimento di Scienze della Salute , Università di Catanzaro , Viale Europa , 88100 Catanzaro , Italy
| | - Massimiliano Bonomi
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , United Kingdom
| | - Adriana Pietropaolo
- Dipartimento di Scienze della Salute , Università di Catanzaro , Viale Europa , 88100 Catanzaro , Italy
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15
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Gali SM, D’Avino G, Aurel P, Han G, Yi Y, Papadopoulos TA, Coropceanu V, Brédas JL, Hadziioannou G, Zannoni C, Muccioli L. Energetic fluctuations in amorphous semiconducting polymers: Impact on charge-carrier mobility. J Chem Phys 2017; 147:134904. [DOI: 10.1063/1.4996969] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Sai Manoj Gali
- Institut des Sciences Moléculaires, UMR 5255, University of Bordeaux, Talence, France
- Laboratoire de Chimie des Polymères Organiques, UMR 5629, University of Bordeaux, Pessac, France
| | - Gabriele D’Avino
- Institut Néel, CNRS and Grenoble Alpes University, Grenoble, France
| | - Philippe Aurel
- Institut des Sciences Moléculaires, UMR 5255, University of Bordeaux, Talence, France
| | - Guangchao Han
- Institute of Chemistry, Chinese Academy of Sciences, Beijing, China
| | - Yuanping Yi
- Institute of Chemistry, Chinese Academy of Sciences, Beijing, China
| | | | - Veaceslav Coropceanu
- Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Jean-Luc Brédas
- Center for Organic Photonics and Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | - Georges Hadziioannou
- Laboratoire de Chimie des Polymères Organiques, UMR 5629, University of Bordeaux, Pessac, France
| | - Claudio Zannoni
- Dipartimento di Chimica Industriale “Toso Montanari,” University of Bologna, Bologna, Italy
| | - Luca Muccioli
- Institut des Sciences Moléculaires, UMR 5255, University of Bordeaux, Talence, France
- Dipartimento di Chimica Industriale “Toso Montanari,” University of Bologna, Bologna, Italy
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16
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Koch M, Myahkostupov M, Oblinsky DG, Wang S, Garakyaraghi S, Castellano FN, Scholes GD. Charge Localization after Ultrafast Photoexcitation of a Rigid Perylene Perylenediimide Dyad Visualized by Transient Stark Effect. J Am Chem Soc 2017; 139:5530-5537. [DOI: 10.1021/jacs.7b01630] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marius Koch
- Department
of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08540, United States
| | - Mykhaylo Myahkostupov
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Daniel G. Oblinsky
- Department
of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08540, United States
| | - Siwei Wang
- Department
of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08540, United States
| | - Sofia Garakyaraghi
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Felix N. Castellano
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Gregory D. Scholes
- Department
of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08540, United States
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17
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Wang M, Zhang X. Ultrafast injection-locked amplification in a thin-film distributed feedback microcavity. NANOSCALE 2017; 9:2689-2694. [PMID: 28182182 DOI: 10.1039/c6nr09973d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Injection mode locking is an important technique to achieve high-performance laser sources. Although this technique has been utilized in conventional laser systems, it has not been applied in thin-film distributed feedback lasers based on nanoscale photonic structures. We demonstrate an ultrafast injection-locked amplifier by injecting femtosecond supercontinuum pulses into a polymer-coated DFB microcavity. The amplifier works in the time scale of picoseconds and a bandwidth of 1 nm, supplying an easily recollimatable laser beam with excellent transverse mode. This introduces a miniaturized and easily integratable laser device for both near-field and far-field applications.
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Affiliation(s)
- Meng Wang
- Institute of Information Photonics Technology and College of Applied Sciences, Beijing University of Technology, Beijing 100124, P. R. China.
| | - Xinping Zhang
- Institute of Information Photonics Technology and College of Applied Sciences, Beijing University of Technology, Beijing 100124, P. R. China.
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18
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Abelha TF, Phillips TW, Bannock JH, Nightingale AM, Dreiss CA, Kemal E, Urbano L, deMello JC, Green M, Dailey LA. Bright conjugated polymer nanoparticles containing a biodegradable shell produced at high yields and with tuneable optical properties by a scalable microfluidic device. NANOSCALE 2017; 9:2009-2019. [PMID: 28106200 DOI: 10.1039/c6nr09162h] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This study compares the performance of a microfluidic technique and a conventional bulk method to manufacture conjugated polymer nanoparticles (CPNs) embedded within a biodegradable poly(ethylene glycol) methyl ether-block-poly(lactide-co-glycolide) (PEG5K-PLGA55K) matrix. The influence of PEG5K-PLGA55K and conjugated polymers cyano-substituted poly(p-phenylene vinylene) (CN-PPV) and poly(9,9-dioctylfluorene-2,1,3-benzothiadiazole) (F8BT) on the physicochemical properties of the CPNs was also evaluated. Both techniques enabled CPN production with high end product yields (∼70-95%). However, while the bulk technique (solvent displacement) under optimal conditions generated small nanoparticles (∼70-100 nm) with similar optical properties (quantum yields ∼35%), the microfluidic approach produced larger CPNs (140-260 nm) with significantly superior quantum yields (49-55%) and tailored emission spectra. CPNs containing CN-PPV showed smaller size distributions and tuneable emission spectra compared to F8BT systems prepared under the same conditions. The presence of PEG5K-PLGA55K did not affect the size or optical properties of the CPNs and provided a neutral net electric charge as is often required for biomedical applications. The microfluidics flow-based device was successfully used for the continuous preparation of CPNs over a 24 hour period. On the basis of the results presented here, it can be concluded that the microfluidic device used in this study can be used to optimize the production of bright CPNs with tailored properties with good reproducibility.
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Affiliation(s)
- T F Abelha
- King's College London, Institute of Pharmaceutical Science, Waterloo Campus, SE1 9NH, London, UK
| | - T W Phillips
- Imperial College London, Department of Chemistry, South Kensington Campus, SW7 2AZ, London, UK
| | - J H Bannock
- Imperial College London, Department of Chemistry, South Kensington Campus, SW7 2AZ, London, UK
| | - A M Nightingale
- Faculty of Engineering and the Environment, University of Southampton, Southampton, UK
| | - C A Dreiss
- King's College London, Institute of Pharmaceutical Science, Waterloo Campus, SE1 9NH, London, UK
| | - E Kemal
- King's College London, Department of Physics, Strand Campus, WC2R 2LS, London, UK.
| | - L Urbano
- King's College London, Institute of Pharmaceutical Science, Waterloo Campus, SE1 9NH, London, UK
| | - J C deMello
- Imperial College London, Department of Chemistry, South Kensington Campus, SW7 2AZ, London, UK
| | - M Green
- King's College London, Department of Physics, Strand Campus, WC2R 2LS, London, UK.
| | - L A Dailey
- Institut für Pharmazeutische Technologie und Biopharmazie, Martin-Luther-Universität Halle-Wittenberg, Halle, Germany.
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19
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Triphenylamine-based electroactive compounds: synthesis, properties and application to organic electronics. CHEMICAL PAPERS 2016. [DOI: 10.1007/s11696-016-0097-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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20
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Denis JC, Ruseckas A, Hedley GJ, Matheson AB, Paterson MJ, Turnbull GA, Samuel IDW, Galbraith I. Self-trapping and excited state absorption in fluorene homo-polymer and copolymers with benzothiadiazole and tri-phenylamine. Phys Chem Chem Phys 2016; 18:21937-48. [DOI: 10.1039/c6cp02059c] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Excited state absorption (ESA) is studied using time-dependent density functional theory and compared with experiments performed in dilute solutions.
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Affiliation(s)
- Jean-Christophe Denis
- Institute of Photonics and Quantum Sciences
- SUPA
- School of Engineering and Physical Sciences
- Heriot-Watt University
- Edinburgh
| | - Arvydas Ruseckas
- Organic Semiconductor Centre
- SUPA
- School of Physics & Astronomy
- University of St. Andrews
- St. Andrews
| | - Gordon J. Hedley
- Organic Semiconductor Centre
- SUPA
- School of Physics & Astronomy
- University of St. Andrews
- St. Andrews
| | - Andrew B. Matheson
- Organic Semiconductor Centre
- SUPA
- School of Physics & Astronomy
- University of St. Andrews
- St. Andrews
| | - Martin J. Paterson
- Institute of Chemical Sciences
- School of Engineering and Physical Sciences
- Heriot-Watt University
- Edinburgh
- UK
| | - Graham A. Turnbull
- Organic Semiconductor Centre
- SUPA
- School of Physics & Astronomy
- University of St. Andrews
- St. Andrews
| | - Ifor D. W. Samuel
- Organic Semiconductor Centre
- SUPA
- School of Physics & Astronomy
- University of St. Andrews
- St. Andrews
| | - Ian Galbraith
- Institute of Photonics and Quantum Sciences
- SUPA
- School of Engineering and Physical Sciences
- Heriot-Watt University
- Edinburgh
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21
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Koch M, Licari G, Vauthey E. Bimodal Exciplex Formation in Bimolecular Photoinduced Electron Transfer Revealed by Ultrafast Time-Resolved Infrared Absorption. J Phys Chem B 2015; 119:11846-57. [PMID: 26264856 DOI: 10.1021/acs.jpcb.5b07663] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The dynamics of a moderately exergonic photoinduced charge separation has been investigated by ultrafast time-resolved infrared absorption with the dimethylanthracene/phthalonitrile donor/acceptor pair in solvents covering a broad range of polarity. A distinct spectral signature of an exciplex could be identified in the -C≡N stretching region. On the basis of quantum chemistry calculations, the 4-5 times larger width of this band compared to those of the ions and of the locally excited donor bands is explained by a dynamic distribution of exciplex geometry with different mutual orientations and distances of the constituents and, thus, with varying charge-transfer character. Although spectrally similar, two types of exciplexes could be distinguished by their dynamics: short-lived, "tight", exciplexes generated upon static quenching and longer-lived, "loose", exciplexes formed upon dynamic quenching in parallel with ion pairs. Tight exciplexes were observed in all solvents, except in the least polar diethyl ether where quenching is slower than diffusion. The product distribution of the dynamic quenching depends strongly on the solvent polarity: whereas no significant loose exciplex population could be detected in acetonitrile, both exciplex and ion pair are generated in less polar solvents, with the relative population of exciplex increasing with decreasing solvent polarity. These results are compared with those reported previously with donor/acceptor pairs in different driving force regimes to obtain a comprehensive picture of the role of the exciplexes in bimolecular photoinduced charge separation.
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Affiliation(s)
- Marius Koch
- Department of Physical Chemistry, University of Geneva , 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Giuseppe Licari
- Department of Physical Chemistry, University of Geneva , 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Eric Vauthey
- Department of Physical Chemistry, University of Geneva , 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
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22
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Hao L, Wang W, Sun Y, Niu H. Synthesis and electrochromic properties of novel poly(urethane–azomethine)s containing triphenylamine units. J Electroanal Chem (Lausanne) 2015. [DOI: 10.1016/j.jelechem.2015.01.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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23
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Niu Q, Sun H, Li X. Synthesis, photophysical and thin-film self-assembly properties of novel fluorescent molecules with carbon-carbon triple bonds. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 133:229-240. [PMID: 24945864 DOI: 10.1016/j.saa.2014.05.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 03/19/2014] [Accepted: 05/16/2014] [Indexed: 06/03/2023]
Abstract
Three novel fluorescent molecules with carbon-carbon triple bonds 2TBEA, 2TBDA and TEPEB are successfully designed and synthesized. Their thermal, photophysical, electrochemical, electronic and thin-film self-assembly properties were characterized. Three dyes showed typical photoluminescence (PL) emission behaviors, the PL intensities firstly increased and then decreased with gradually decreasing concentration. The appealing fluorescence properties indicated that three dyes could be used as good fluorescent materials. Additionally, the thin-film self-assembly behaviors of three dyes were also investigated. The microstructures of their optical microscopy (OM) images exhibited high flexibility. Furthermore, SEM and AFM surface morphology of these self-assembly nanostructures revealed that three well-defined long-range order of rod-like and tube-like self-assembly systems exhibited interesting morphology properties. Therefore, three compounds may be of great interest for the development of organic thin-film materials.
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Affiliation(s)
- Qingfen Niu
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250199 Jinan, People's Republic of China
| | - Hongjian Sun
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250199 Jinan, People's Republic of China
| | - Xiaoyan Li
- School of Chemistry and Chemical Engineering, Key Laboratory of Special Functional Aggregated Materials, Ministry of Education, Shandong University, Shanda Nanlu 27, 250199 Jinan, People's Republic of China.
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24
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Lochner CM, Khan Y, Pierre A, Arias AC. All-organic optoelectronic sensor for pulse oximetry. Nat Commun 2014; 5:5745. [PMID: 25494220 DOI: 10.1038/ncomms6745] [Citation(s) in RCA: 244] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 11/03/2014] [Indexed: 12/11/2022] Open
Abstract
Pulse oximetry is a ubiquitous non-invasive medical sensing method for measuring pulse rate and arterial blood oxygenation. Conventional pulse oximeters use expensive optoelectronic components that restrict sensing locations to finger tips or ear lobes due to their rigid form and area-scaling complexity. In this work, we report a pulse oximeter sensor based on organic materials, which are compatible with flexible substrates. Green (532 nm) and red (626 nm) organic light-emitting diodes (OLEDs) are used with an organic photodiode (OPD) sensitive at the aforementioned wavelengths. The sensor's active layers are deposited from solution-processed materials via spin-coating and printing techniques. The all-organic optoelectronic oximeter sensor is interfaced with conventional electronics at 1 kHz and the acquired pulse rate and oxygenation are calibrated and compared with a commercially available oximeter. The organic sensor accurately measures pulse rate and oxygenation with errors of 1% and 2%, respectively.
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Affiliation(s)
- Claire M Lochner
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA
| | - Yasser Khan
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA
| | - Adrien Pierre
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA
| | - Ana C Arias
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA
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25
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Ndesendo VMK, Choonara YE, Meyer LCR, Kumar P, Tomar LK, Tyagi C, du Toit LC, Pillay V. In vivo evaluation of a mucoadhesive polymeric caplet for intravaginal anti-HIV-1 delivery and development of a molecular mechanistic model for thermochemical characterization. Drug Dev Ind Pharm 2014; 41:1274-87. [PMID: 25109400 DOI: 10.3109/03639045.2014.947506] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
CONTEXT AND OBJECTIVE The aim of this study was to develop, characterize and evaluate a mucoadhesive caplet resulting from a polymeric blend (polymeric caplet) for intravaginal anti-HIV-1 delivery. MATERIALS AND METHODS Poly(lactic-co-glycolic) acid, ethylcellulose, poly(vinylalcohol), polyacrylic acid and modified polyamide 6, 10 polymers were blended and compressed to a caplet-shaped device, with and without two model drugs 3'-azido-3'-deoxythymidine (AZT) and polystyrene sulfonate (PSS). Thermal analysis, infrared spectroscopy and microscopic analysis were carried out on the caplets employing temperature-modulated DSC (TMDSC), Fourier transform infra-red (FTIR) spectrometer and scanning electron microscope, respectively. In vitro and in vivo drug release analyses as well as the histopathological toxicity studies were carried out on the drug-loaded caplets. Furthermore, molecular mechanics (MM) simulations were carried out on the drug-loaded caplets to corroborate the experimental findings. RESULTS AND DISCUSSION There was a big deviation between the Tg of the polymeric caplet from the Tg's of the constituent polymers indicating a strong interaction between constituent polymers. FTIR spectroscopy confirmed the presence of specific ionic and non-ionic interactions within the caplet. A controlled near zero-order drug release was obtained for AZT (20 d) and PSS (28 d). In vivo results, i.e. the drug concentration in plasma ranged between 0.012-0.332 mg/mL and 0.009-0.256 mg/mL for AZT and PSS over 1-28 d. CONCLUSION The obtained results, which were corroborated by MM simulations, attested that the developed system has the potential for effective delivery of anti-HIV-agents.
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Affiliation(s)
- Valence M K Ndesendo
- Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, Faculty of Health Sciences, School of Therapeutic Sciences, University of the Witwatersrand , Johannesburg, Parktown , South Africa
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26
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Koch M, Letrun R, Vauthey E. Exciplex Formation in Bimolecular Photoinduced Electron-Transfer Investigated by Ultrafast Time-Resolved Infrared Spectroscopy. J Am Chem Soc 2014; 136:4066-74. [DOI: 10.1021/ja500812u] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Marius Koch
- Department
of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Romain Letrun
- Department
of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Eric Vauthey
- Department
of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
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27
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Dou F, Silva C, Zhang X. The role of acceptor-rich domain in optoelectronic properties of photovoltaic diodes based on polymer blends. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2013.07.049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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28
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Yang PC, Wu H, Wen HW, Hung WN. Synthesis, characterization, and ion responsive properties of hyperbranched oligofluorene using carbazole as a branching core. Eur Polym J 2013. [DOI: 10.1016/j.eurpolymj.2013.05.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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29
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Zhang L, Wang Y, Sui N, Kang Z, Huang T, Ma Y, Zhang H. Theoretical and Experimental Study of Photophysical Characteristics between Poly(9,9‐dioctylfluorene) and Poly(9,9‐dioctylfluorene‐cobenzothiadiazole). CHINESE J CHEM PHYS 2013. [DOI: 10.1063/1674-0068/26/04/387-392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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30
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Dou F, Silva C, Zhang X. Charge percolation pathways in polymer blend photovoltaic diodes with sub-mesoscopic two-phase microstructures. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2013.03.076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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31
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Kimura M, Karasawa M, Sasagawa N, Takemoto K, Goto R, Mori S. Organic Sensitizers Including π-Conjugated Fluorene–Benzothiadiazole Bridge for Dye-sensitized Solar Cells. CHEM LETT 2012. [DOI: 10.1246/cl.2012.1613] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Mutsumi Kimura
- Faculty of Textile Science and Technology, Shinshu University
| | | | - Naoki Sasagawa
- Faculty of Textile Science and Technology, Shinshu University
| | | | - Ryota Goto
- Faculty of Textile Science and Technology, Shinshu University
| | - Shogo Mori
- Faculty of Textile Science and Technology, Shinshu University
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32
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Gélinas S, Kirkpatrick J, Howard IA, Johnson K, Wilson MWB, Pace G, Friend RH, Silva C. Recombination Dynamics of Charge Pairs in a Push–Pull Polyfluorene-Derivative. J Phys Chem B 2012; 117:4649-53. [DOI: 10.1021/jp3089963] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Simon Gélinas
- Département de Physique & Regroupement Québécois sur les Matériaux de Pointe, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada
- Cavendish
Laboratory, University of Cambridge, J.J.
Thompson Avenue, Cambridge
CB3 0HE, United Kingdom
| | - James Kirkpatrick
- Oxford
Martin School, University of Oxford, Oxford
OX1 2JD, United Kingdom
| | - Ian A. Howard
- Max Planck Institute for Polymer Research, D-55128 Mainz, Germany
| | - Kerr Johnson
- Cavendish
Laboratory, University of Cambridge, J.J.
Thompson Avenue, Cambridge
CB3 0HE, United Kingdom
| | - Mark W. B. Wilson
- Cavendish
Laboratory, University of Cambridge, J.J.
Thompson Avenue, Cambridge
CB3 0HE, United Kingdom
| | - Giuseppina Pace
- Cavendish
Laboratory, University of Cambridge, J.J.
Thompson Avenue, Cambridge
CB3 0HE, United Kingdom
| | - Richard H. Friend
- Cavendish
Laboratory, University of Cambridge, J.J.
Thompson Avenue, Cambridge
CB3 0HE, United Kingdom
| | - Carlos Silva
- Département de Physique & Regroupement Québécois sur les Matériaux de Pointe, Université de Montréal, C.P. 6128, Succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada
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33
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Li Y, Lagowski JB. A multi-step simulation of electron mobility in fluorene–benzothiadiazole conjugated polymer – Case study. COMPUT THEOR CHEM 2011. [DOI: 10.1016/j.comptc.2011.09.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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34
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Lee LT, Ube T, Aoki H, Ito S. Characterization of surface compositions of phase-separated structures in conjugated poly(phenylene vinylene) blends by scanning near-field optical microscopy. POLYMER 2011. [DOI: 10.1016/j.polymer.2011.10.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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35
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Fan H, Zhang Z, Li Y, Zhan X. Copolymers of fluorene and thiophene with conjugated side chain for polymer solar cells: Effect of pendant acceptors. ACTA ACUST UNITED AC 2011. [DOI: 10.1002/pola.24568] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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36
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Quarti C, Fazzi D, Del Zoppo M. A computational investigation on singlet and triplet exciton couplings in acene molecular crystals. Phys Chem Chem Phys 2011; 13:18615-25. [DOI: 10.1039/c1cp21246j] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Tsutsumi J, Yamada T, Matsui H, Haas S, Hasegawa T. Competition between charge-transfer exciton dissociation and direct photocarrier generation in molecular donor-acceptor compounds. PHYSICAL REVIEW LETTERS 2010; 105:226601. [PMID: 21231409 DOI: 10.1103/physrevlett.105.226601] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Indexed: 05/30/2023]
Abstract
The interfacial charge-separation and photovoltaic characteristics of a molecular donor-acceptor charge-transfer compound were examined. Measurements of laser beam-induced currents on the single crystals allowed selective detection of hole and electron photocurrents through the metal-semiconductor interfaces. This method also reveals the exceptionally long diffusion length of 20 μm in the crystal. The transition from charge-transfer exciton dissociation to direct photocarrier generation is discussed on the basis of the photon-energy-dependent diffusion length and photon-to-current conversion spectrum.
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Affiliation(s)
- Jun'ya Tsutsumi
- Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan
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38
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Qi Y, Liu X, Hendriksen BLM, Navarro V, Park JY, Ratera I, Klopp JM, Edder C, Himpsel FJ, Fréchet JMJ, Haller EE, Salmeron M. Influence of molecular ordering on electrical and friction properties of ω-(trans-4-stilbene)alkylthiol self-assembled monolayers on Au(111). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:16522-16528. [PMID: 20415505 DOI: 10.1021/la100837g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The electrical and friction properties of ω-(trans-4-stilbene)alkylthiol self-assembled monolayers (SAMs) on Au(111) were investigated using atomic force microscopy (AFM) and near edge X-ray absorption fine structure spectroscopy (NEXAFS). The sample surface was uniformly covered with a molecular film consisting of very small grains. Well-ordered and flat monolayer islands were formed after the sample was heated in nitrogen at 120 °C for 1 h. While lattice resolved AFM images revealed a crystalline phase in the islands, the area between islands showed no order. The islands exhibit substantial reduction (50%) in friction, supporting the existence of good ordering. NEXAFS measurements revealed an average upright molecular orientation in the film, both before and after heating, with a narrower tilt-angle distribution for the heated fim. Conductance-AFM measurements revealed a 2 orders of magnitude higher conductivity on the ordered islands than on the disordered phase. We propose that the conductance enhancement is a result of a better π-π stacking between the trans-stilbene molecular units as a result of improved ordering in islands.
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Affiliation(s)
- Yabing Qi
- Applied Science and Technology Graduate Group, University of California, Berkeley, California 94720, USA
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Linder T, Badiola E, Baumgartner T, Sutherland TC. Synthesis of π-Extended Thiadiazole (Oxides) and Their Electronic Properties. Org Lett 2010; 12:4520-3. [DOI: 10.1021/ol1018213] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas Linder
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
| | - Eider Badiola
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
| | - Thomas Baumgartner
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
| | - Todd C. Sutherland
- Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4
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40
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Chen WH, Wang KL, Hung WY, Jiang JC, Liaw DJ, Lee KR, Lai JY, Chen CL. Novel triarylamine-based alternating conjugated polymer with high hole mobility: Synthesis, electro-optical, and electronic properties. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/pola.24252] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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41
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Multichromophoric Phthalocyanine-(Perylenediimide)8Molecules: A Photophysical Study. Chemistry 2010; 16:10021-9. [DOI: 10.1002/chem.201000677] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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42
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Zhang R, Du B, Sun G, Sun Y. Experimental and theoretical studies on o-, m- and p-chlorobenzylideneaminoantipyrines. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010; 75:1115-1124. [PMID: 20093073 DOI: 10.1016/j.saa.2009.12.067] [Citation(s) in RCA: 183] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2009] [Revised: 12/18/2009] [Accepted: 12/24/2009] [Indexed: 05/28/2023]
Abstract
Three antipyrine derivatives of o-, m- and p-chlorobenzylideneaminoantipyrines were characterized by spectral techniques and density functional calculations. The optimized configurations are very close to the XRD values and are used as foundations to investigate the molecular properties. The spectral assignments were attempted to ascribe to the vibrational modes of the detailed substructures with the aid of theoretical calculations because of the satisfactory consistencies between the experimental and theoretical spectra for each of the studied compounds. Raman spectral ascriptions represent that the pi-conjugated moieties linked by Schiff base imines are responsible for the excellent Raman scattering activities of these compounds. The linear polarizabilities and first hyperpolarizabilities of the studied molecules indicate that the compounds are good candidates of nonlinear optical materials. The statistical thermodynamic functions and their correlations with temperatures obtained from the theoretical vibrations are similar to each other among the isomers.
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Affiliation(s)
- Ran Zhang
- Institute for Material Chemistry, Binzhou University, Binzhou, PR China
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43
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Yim KH, Doherty WJ, Salaneck WR, Murphy CE, Friend RH, Kim JS. Phase-separated thin film structures for efficient polymer blend light-emitting diodes. NANO LETTERS 2010; 10:385-392. [PMID: 20102212 DOI: 10.1021/nl9025105] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report laterally and vertically phase-separated thin film structures in conjugated polymer blends created by polymer molecular weight variation. We find that micrometer-scale lateral phase separation is critical in achieving high initial device efficiency of light-emitting diodes, whereas improved balance of charge carrier mobilities and film thickness uniformity are important in maintaining high efficiency at high voltages. The optoelectronic properties of these blend thin films and devices are strongly influenced by the polymer chain order/disorder and the interface state formed at polymer/polymer heterojunctions.
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Affiliation(s)
- Keng-Hoong Yim
- Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, UK
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44
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Chen WH, Wang KL, Liaw DJ, Lee KR, Lai JY. N,N,N′,N′- Tetraphenyl-1,4-phenylenediamine−Fluorene Alternating Conjugated Polymer: Synthesis, Characterization, and Electrochromic Application. Macromolecules 2010. [DOI: 10.1021/ma902138g] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Wen-Hsiang Chen
- Department of Chemical Engineering, National Taiwan University of Science and Technology, 10607 Taipei, Taiwan
| | - Kun-Li Wang
- Department of Chemical Engineering and Biotechnology, National Taipei University of Technology, 10608 Taipei, Taiwan
| | - Der-Jang Liaw
- Department of Chemical Engineering, National Taiwan University of Science and Technology, 10607 Taipei, Taiwan
| | - Kueir-Rarn Lee
- R&D Center for Membrane Technology, Department of Chemical Engineering, Chung Yuan University, 32023 Chung-Li, Taiwan
| | - Juin-Yih Lai
- R&D Center for Membrane Technology, Department of Chemical Engineering, Chung Yuan University, 32023 Chung-Li, Taiwan
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45
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Sun YX, Hao QL, Lu LD, Wang X, Yang XJ. Vibrational spectroscopic study of o-, m- and p-hydroxybenzylideneaminoantipyrines. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010; 75:203-211. [PMID: 19913456 DOI: 10.1016/j.saa.2009.10.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 10/01/2009] [Accepted: 10/08/2009] [Indexed: 05/28/2023]
Abstract
Three structurally similar antipyrine derivatives of o-hydroxybenzylideneaminoantipyrine (o-HBAP), m-hydroxybenzylideneaminoantipyrine (m-HBAP) and p-hydroxybenzylideneaminoantipyrine (p-HBAP) were characterized by FT-IR, FT-Raman experimental techniques and density functional theoretical (DFT) calculations. The comparisons between the calculated and experimental results covering molecular structures, assignments of fundamental vibrational modes and thermodynamic properties were investigated. The optimized molecular geometries agree well with the corresponding experimental values by comparing with the XRD data. The comparisons and assignments of the vibrational frequencies indicate that the experimental spectra also coincide satisfactorily with those of theoretically simulated spectrograms except the hydrogen-bond coupling infrared vibrations, and compounds can be distinguished by the IR and Raman spectra due to the differences of the hydroxyl-substituted positions and molecular packing, and the strong Raman scattering activities of the compounds are tightly relative to the molecular conjugative moieties linked through the Schiff base imines. The thermodynamic functions and their correlations with temperatures were also obtained from the theoretical harmonic frequencies.
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Affiliation(s)
- Yu-Xi Sun
- Key Laboratory of Education Ministry for Soft Chemistry and Functional Materials, Nanjing University of Science and Technology, Nanjing, PR China.
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46
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Lin Y, Chen ZK, Ye TL, Dai YF, Ma DG, Ma Z, Liu QD, Chen Y. Conjugated copolymers comprised cyanophenyl-substituted spirobifluorene and tricarbazole-triphenylamine repeat units for blue-light-emitting diodes. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/pola.23783] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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47
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Michinobu T, Kumazawa H, Otsuki E, Usui H, Shigehara K. Synthesis and properties of nitrogen-linked poly(2,7-carbazole)s as hole-transport material for organic light emitting diodes. ACTA ACUST UNITED AC 2009. [DOI: 10.1002/pola.23454] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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48
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Hodgkiss JM, Tu G, Albert-Seifried S, Huck WTS, Friend RH. Ion-Induced Formation of Charge-Transfer States in Conjugated Polyelectrolytes. J Am Chem Soc 2009; 131:8913-21. [DOI: 10.1021/ja902167a] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Justin M. Hodgkiss
- Cavendish Laboratory, Department of Physics, University of Cambridge, CB3 0HE, U.K., and Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, CB2 1EW, U.K
| | - Guoli Tu
- Cavendish Laboratory, Department of Physics, University of Cambridge, CB3 0HE, U.K., and Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, CB2 1EW, U.K
| | - Sebastian Albert-Seifried
- Cavendish Laboratory, Department of Physics, University of Cambridge, CB3 0HE, U.K., and Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, CB2 1EW, U.K
| | - Wilhelm T. S. Huck
- Cavendish Laboratory, Department of Physics, University of Cambridge, CB3 0HE, U.K., and Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, CB2 1EW, U.K
| | - Richard H. Friend
- Cavendish Laboratory, Department of Physics, University of Cambridge, CB3 0HE, U.K., and Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge, CB2 1EW, U.K
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49
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Zhang ZG, Zhang KL, Liu G, Zhu CX, Neoh KG, Kang ET. Triphenylamine−Fluorene Alternating Conjugated Copolymers with Pendant Acceptor Groups: Synthesis, Structure−Property Relationship, and Photovoltaic Application. Macromolecules 2009. [DOI: 10.1021/ma900236h] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Zhi-Guo Zhang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People’s Republic of China, and Departments of Chemical & Biomolecular Engineering and Electrical & Computer Engineering, National University of Singapore, Kent Ridge, Singapore 119260
| | - Ke-Li Zhang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People’s Republic of China, and Departments of Chemical & Biomolecular Engineering and Electrical & Computer Engineering, National University of Singapore, Kent Ridge, Singapore 119260
| | - Gang Liu
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People’s Republic of China, and Departments of Chemical & Biomolecular Engineering and Electrical & Computer Engineering, National University of Singapore, Kent Ridge, Singapore 119260
| | - Chun-Xiang Zhu
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People’s Republic of China, and Departments of Chemical & Biomolecular Engineering and Electrical & Computer Engineering, National University of Singapore, Kent Ridge, Singapore 119260
| | - Koon-Gee Neoh
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People’s Republic of China, and Departments of Chemical & Biomolecular Engineering and Electrical & Computer Engineering, National University of Singapore, Kent Ridge, Singapore 119260
| | - En-Tang Kang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People’s Republic of China, and Departments of Chemical & Biomolecular Engineering and Electrical & Computer Engineering, National University of Singapore, Kent Ridge, Singapore 119260
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50
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Dufresne S, Pérez Guarìn SA, Bolduc A, Bourque AN, Skene WG. Conjugated fluorene-thiophenes prepared from azomethine connections : Part I. The effect of electronic and aryl groups on the spectroscopic and electrochemical properties. Photochem Photobiol Sci 2009; 8:796-804. [DOI: 10.1039/b819735k] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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